An Internet WebQuest
Have you ever visited the primate house at a local zoo or watched a television program about primates? Many people are
amused at the antics of gorillas, chimpanzees, monkeys, and lemurs as they eat, play, and explore. Did you know that humans
are primates, too? All primates have opposable thumbs, a relatively large brain, good binocular vision, and flexible joints.
The earliest primates were prosimians, a group that includes present-day lemurs. Humanlike primates were called anthropoids.
Present-day anthropoids include the monkeys and the hominids—apes and humans. Although humans, gorillas, and chimpanzees
are close cousins genetically, humans did not evolve from the great apes. Instead, humans and apes probably evolved from a
common ancestor between 8 and 5 million years ago. These two different groups formed the hominids – primates that can
walk upright on two legs. Whereas the apes continued to evolve into the gorillas, chimpanzees, bonobos, orangutans, and gibbons
of today, humans followed a different path. What hominids were the ancestors of present-day humans? How long ago did human
ancestors split off from the rest of the hominids? Where did humans first evolve? Why is there just one species of humans
alive today? These are some of the questions you will explore in this WebQuest on hominid fossils.
Your job in this WebQuest is to learn all about the evolution of humans. You will learn about the earliest hominids that
may be part of the evolution of humans, and about the fossils that have been found which support this idea. You will look
at photographs of these fossils and read about their similarities and differences. You will find out how scientists have pieced
together the story of human evolution, and discover that the story is far from complete. You will fill in a table that lists
which hominids play a part in human evolution. Finally, you will answer a few questions about hominid fossils to demonstrate
what you have learned in your Internet research.
Look at the web sites given here to find the information that will enable you to complete your table on hominid fossils
and answer a few questions.
- Prominent Hominid Fossils. Visit this site for a comprehensive listing of all hominid fossils that are important either for their scientific or
historic interest. Scroll down and click on any photo to see a larger image and a description of the fossil.
- The Evidence: Hominid Fossils. Go to this University of Texas site to learn about the more important hominid fossils and what they can tell us about
the evolution of humans. This is a very interesting site.
- Human Evolution. Visit this site to see a proposed chart of human evolution from 5 million years ago to the present. This chart illustrates
the best fit for known fossil specimens to date, but it is not accepted totally. As new fossils are found, they tend to impact
thoughts about human evolution.
- Human Evolution: The fossil evidence in 3D. Go to this site for an interactive comparison of the crania of five modern and five fossil primates. You will need shockwave
plugin (available here) to view the gallery. Hold down the lefthand button on your mouse and move the cursor over each photograph
to see the front and side views of each cranium.
- A Science Odyssey: You Try It: Human Evolution Activity. At this site you can use your mouse to move through a timeline of human evolution. You can stop at any time from 5 million
years ago to the present to learn about the hominid species that may, or may not, be a part of human ancestry
- Early Human Evolution. Visit this site by Palomar College, San Marcos, California for an online course on human evolution. Click on early
transitional humans to learn more about the earliest hominid species. Then scroll down and click on nest topic to read more
about Homo erectus.
- Human Ancestry: Species. Go to this site to see a timeline with the hominid species from each time period. Click on any highlighted species name
to read a short article about that species. This is a very detailed and excellent site.
- Early Human Phylogeny. At this Smithsonian Institution site you can see another timeline showing the evolution of hominids over the last
5 million years. Scroll down and click on any species name to learn more about that species. Or you can click on catalog to
see a particular specimen in the National Museum of Natural History’s collection.
- New Hominid Species Complicates Early Hominid Evolution. Visit this site to read about a 3.5 million-year-old skull found in Kenya in 1998-1999. This skull is a new species called
Kenyanthropus platyops. It is strikingly different from Australopithecus afarensis fossils from the same place
and time period.
- Guided Tour – Hominid Evolution. At this site you can learn about the earliest hominids and see photographs of the fossils. You can also learn more
about associated topics, such as bipedalism, at this site.
2 class periods for research, filling in the table, and answering a few questions
Now that you have completed your research on hominid fossils, prepare a table like the one below with the information that
you have gathered on each of the species listed. For each species, list the location in which the first fossils of its type
were found and the estimated age of that fossil. You will need to look at all of the web sites listed in order to complete
the table. Once the table has been filled in, answer the questions that follow.
Table 1. Hominid Fossils
|Genus and species
||Location of Fossil
||Estimated Age of Fossil|
Questions about Hominid Fossils
- A new species named Kenyanthropus platyops was found recently in Kenya. Between what two species would you place
this species in the above table, and why?
- Another new species was discovered in Ethiopia in 1999. What is the genus and species of this fossil? Where would you
place it in the above table?
- Name three of the clear trends in the evolution of hominids from early australopithecines to recent humans. For example,
one clear trend is increasing brain size.
- Which step in hominid evolution came first – bipedal locomotion or larger brains? How do scientists know this?
- What happened about 8 to 5 million years ago in Africa that may have led to the development of many different species
- Why are Neanderthals sometimes given the name Homo sapiens neanderthalensis?
- Why is there still so much controversy over the evolution of humans from hominids?
In the process of completing this WebQuest, you’ve become informed about the hominid fossils that may be part of
the story of human evolution. You have learned about many hominid fossils and the species they represent. You have developed
critical thinking skills as you explored the environmental changes that may have led to the evolution of bipedal hominids.
Do you think scientists have enough information to draw a clear timeline of the evolution of humans?